overlayfs: overlapping lowerdir path overlayfs: overlapping lowerdir path overlayfs: overlapping lowerdir path overlayfs: overlapping lowerdir path ====================================================== WARNING: possible circular locking dependency detected 4.19.211-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.5/15615 is trying to acquire lock: 000000008370e60b (&ovl_i_mutex_dir_key[depth]){++++}, at: inode_lock_shared include/linux/fs.h:758 [inline] 000000008370e60b (&ovl_i_mutex_dir_key[depth]){++++}, at: do_last fs/namei.c:3326 [inline] 000000008370e60b (&ovl_i_mutex_dir_key[depth]){++++}, at: path_openat+0x17ec/0x2df0 fs/namei.c:3537 but task is already holding lock: 0000000011dac8d1 (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds fs/exec.c:1419 [inline] 0000000011dac8d1 (&sig->cred_guard_mutex){+.+.}, at: __do_execve_file+0x38c/0x2360 fs/exec.c:1762 PM: Basic memory bitmaps created which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&sig->cred_guard_mutex){+.+.}: lock_trace fs/proc/base.c:402 [inline] proc_pid_stack+0x160/0x350 fs/proc/base.c:452 proc_single_show+0xeb/0x170 fs/proc/base.c:755 seq_read+0x4e0/0x11c0 fs/seq_file.c:232 __vfs_read+0xf7/0x750 fs/read_write.c:416 vfs_read+0x194/0x3c0 fs/read_write.c:452 ksys_read+0x12b/0x2a0 fs/read_write.c:579 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #2 (&p->lock){+.+.}: overlayfs: 'file0' not a directory seq_read+0x6b/0x11c0 fs/seq_file.c:164 proc_reg_read+0x1bd/0x2d0 fs/proc/inode.c:231 do_loop_readv_writev fs/read_write.c:701 [inline] do_loop_readv_writev fs/read_write.c:688 [inline] do_iter_read+0x471/0x630 fs/read_write.c:925 vfs_readv+0xe5/0x150 fs/read_write.c:987 mac80211_hwsim: wmediumd released netlink socket, switching to perfect channel medium kernel_readv fs/splice.c:362 [inline] default_file_splice_read+0x457/0xa00 fs/splice.c:417 do_splice_to+0x10e/0x160 fs/splice.c:881 splice_direct_to_actor+0x2b9/0x8d0 fs/splice.c:959 do_splice_direct+0x1a7/0x270 fs/splice.c:1068 PM: Basic memory bitmaps freed do_sendfile+0x550/0xc30 fs/read_write.c:1447 __do_sys_sendfile64 fs/read_write.c:1508 [inline] __se_sys_sendfile64+0x147/0x160 fs/read_write.c:1494 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #1 (sb_writers#3){.+.+}: sb_start_write include/linux/fs.h:1579 [inline] mnt_want_write+0x3a/0xb0 fs/namespace.c:360 ovl_create_object+0x96/0x290 fs/overlayfs/dir.c:602 lookup_open+0x893/0x1a20 fs/namei.c:3235 overlayfs: 'file0' not a directory do_last fs/namei.c:3327 [inline] path_openat+0x1094/0x2df0 fs/namei.c:3537 do_filp_open+0x18c/0x3f0 fs/namei.c:3567 do_sys_open+0x3b3/0x520 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (&ovl_i_mutex_dir_key[depth]){++++}: down_read+0x36/0x80 kernel/locking/rwsem.c:24 inode_lock_shared include/linux/fs.h:758 [inline] do_last fs/namei.c:3326 [inline] path_openat+0x17ec/0x2df0 fs/namei.c:3537 do_filp_open+0x18c/0x3f0 fs/namei.c:3567 overlayfs: 'file0' not a directory do_open_execat+0x11d/0x5b0 fs/exec.c:853 __do_execve_file+0x1a8b/0x2360 fs/exec.c:1770 do_execveat_common fs/exec.c:1879 [inline] do_execve+0x35/0x50 fs/exec.c:1896 __do_sys_execve fs/exec.c:1977 [inline] __se_sys_execve fs/exec.c:1972 [inline] __x64_sys_execve+0x7c/0xa0 fs/exec.c:1972 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 overlayfs: 'file0' not a directory entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Chain exists of: &ovl_i_mutex_dir_key[depth] --> &p->lock --> &sig->cred_guard_mutex Possible unsafe locking scenario: overlayfs: 'file0' not a directory CPU0 CPU1 ---- ---- lock(&sig->cred_guard_mutex); lock(&p->lock); lock(&sig->cred_guard_mutex); lock(&ovl_i_mutex_dir_key[depth]); *** DEADLOCK *** 1 lock held by syz-executor.5/15615: #0: 0000000011dac8d1 (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds fs/exec.c:1419 [inline] #0: 0000000011dac8d1 (&sig->cred_guard_mutex){+.+.}, at: __do_execve_file+0x38c/0x2360 fs/exec.c:1762 overlayfs: 'file0' not a directory stack backtrace: CPU: 1 PID: 15615 Comm: syz-executor.5 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1222 IPVS: ftp: loaded support on port[0] = 21 check_prev_add kernel/locking/lockdep.c:1866 [inline] check_prevs_add kernel/locking/lockdep.c:1979 [inline] validate_chain kernel/locking/lockdep.c:2420 [inline] __lock_acquire+0x30c9/0x3ff0 kernel/locking/lockdep.c:3416 overlayfs: 'file0' not a directory lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3908 down_read+0x36/0x80 kernel/locking/rwsem.c:24 inode_lock_shared include/linux/fs.h:758 [inline] do_last fs/namei.c:3326 [inline] path_openat+0x17ec/0x2df0 fs/namei.c:3537 overlayfs: 'file0' not a directory do_filp_open+0x18c/0x3f0 fs/namei.c:3567 overlayfs: 'file0' not a directory do_open_execat+0x11d/0x5b0 fs/exec.c:853 overlayfs: 'file0' not a directory __do_execve_file+0x1a8b/0x2360 fs/exec.c:1770 overlayfs: 'file0' not a directory do_execveat_common fs/exec.c:1879 [inline] do_execve+0x35/0x50 fs/exec.c:1896 __do_sys_execve fs/exec.c:1977 [inline] __se_sys_execve fs/exec.c:1972 [inline] __x64_sys_execve+0x7c/0xa0 fs/exec.c:1972 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 overlayfs: 'file0' not a directory entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7ffb85c96209 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffb845ea168 EFLAGS: 00000246 ORIG_RAX: 000000000000003b RAX: ffffffffffffffda RBX: 00007ffb85da9030 RCX: 00007ffb85c96209 RDX: 0000000020000b00 RSI: 0000000000000000 RDI: 0000000020000600 RBP: 00007ffb85cf0161 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd3fbd9b7f R14: 00007ffb845ea300 R15: 0000000000022000 netlink: 32 bytes leftover after parsing attributes in process `syz-executor.2'. overlayfs: 'file0' not a directory netlink: 12 bytes leftover after parsing attributes in process `syz-executor.2'. overlayfs: './file0' not a directory netlink: 32 bytes leftover after parsing attributes in process `syz-executor.2'. PM: Marking nosave pages: [mem 0x00000000-0x00000fff] PM: Marking nosave pages: [mem 0x0009f000-0x000fffff] PM: Marking nosave pages: [mem 0xbfffd000-0xffffffff] netlink: 12 bytes leftover after parsing attributes in process `syz-executor.2'. PM: Basic memory bitmaps created PM: Basic memory bitmaps freed IPVS: ftp: loaded support on port[0] = 21 PM: Marking nosave pages: [mem 0x00000000-0x00000fff] PM: Marking nosave pages: [mem 0x0009f000-0x000fffff] PM: Marking nosave pages: [mem 0xbfffd000-0xffffffff] PM: Basic memory bitmaps created PM: Basic memory bitmaps freed PM: Marking nosave pages: [mem 0x00000000-0x00000fff] PM: Marking nosave pages: [mem 0x0009f000-0x000fffff] PM: Marking nosave pages: [mem 0xbfffd000-0xffffffff] PM: Basic memory bitmaps created IPVS: ftp: loaded support on port[0] = 21 PM: Basic memory bitmaps freed PM: Marking nosave pages: [mem 0x00000000-0x00000fff] PM: Marking nosave pages: [mem 0x0009f000-0x000fffff] PM: Marking nosave pages: [mem 0xbfffd000-0xffffffff] PM: Basic memory bitmaps created 9pnet: p9_fd_create_tcp (15880): problem connecting socket to 127.0.0.1 PM: Basic memory bitmaps freed vxfs: WRONG superblock magic 00000000 at 1 PM: Marking nosave pages: [mem 0x00000000-0x00000fff] vxfs: WRONG superblock magic 00000000 at 8 9pnet: p9_fd_create_tcp (15922): problem connecting socket to 127.0.0.1 vxfs: can't find superblock. PM: Marking nosave pages: [mem 0x0009f000-0x000fffff] PM: Marking nosave pages: [mem 0xbfffd000-0xffffffff] PM: Basic memory bitmaps created 9pnet: p9_fd_create_tcp (15963): problem connecting socket to 127.0.0.1 vxfs: WRONG superblock magic 00000000 at 1 PM: Basic memory bitmaps freed vxfs: WRONG superblock magic 00000000 at 8 vxfs: can't find superblock. audit: type=1800 audit(1659322321.687:16341): pid=16009 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.4" name="bus" dev="sda1" ino=14402 res=0 audit: type=1804 audit(1659322321.707:16342): pid=16009 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir1028905005/syzkaller.frGPjC/967/bus" dev="sda1" ino=14402 res=1 vxfs: WRONG superblock magic 00000000 at 1 vxfs: WRONG superblock magic 00000000 at 8 vxfs: can't find superblock. audit: type=1800 audit(1659322321.827:16343): pid=16032 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.4" name="bus" dev="sda1" ino=14195 res=0 audit: type=1800 audit(1659322321.827:16344): pid=16032 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.4" name="bus" dev="sda1" ino=14195 res=0 audit: type=1800 audit(1659322321.827:16345): pid=16032 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.4" name="bus" dev="sda1" ino=14195 res=0 audit: type=1800 audit(1659322321.827:16346): pid=16032 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.4" name="bus" dev="sda1" ino=14195 res=0 audit: type=1800 audit(1659322321.827:16347): pid=16032 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.4" name="bus" dev="sda1" ino=14195 res=0 audit: type=1800 audit(1659322321.827:16348): pid=16032 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.4" name="bus" dev="sda1" ino=14195 res=0 audit: type=1800 audit(1659322321.827:16349): pid=16032 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.4" name="bus" dev="sda1" ino=14195 res=0 audit: type=1800 audit(1659322321.827:16350): pid=16032 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.4" name="bus" dev="sda1" ino=14195 res=0 netlink: 'syz-executor.4': attribute type 1 has an invalid length. PM: Marking nosave pages: [mem 0x00000000-0x00000fff] PM: Marking nosave pages: [mem 0x0009f000-0x000fffff] PM: Marking nosave pages: [mem 0xbfffd000-0xffffffff] PM: Basic memory bitmaps created netlink: 'syz-executor.4': attribute type 1 has an invalid length. netlink: 'syz-executor.4': attribute type 1 has an invalid length. PM: Basic memory bitmaps freed PM: Marking nosave pages: [mem 0x00000000-0x00000fff] PM: Marking nosave pages: [mem 0x0009f000-0x000fffff] PM: Marking nosave pages: [mem 0xbfffd000-0xffffffff] PM: Basic memory bitmaps created PM: Basic memory bitmaps freed PM: Marking nosave pages: [mem 0x00000000-0x00000fff] PM: Marking nosave pages: [mem 0x0009f000-0x000fffff] PM: Marking nosave pages: [mem 0xbfffd000-0xffffffff] PM: Basic memory bitmaps created PM: Basic memory bitmaps freed netlink: 4 bytes leftover after parsing attributes in process `syz-executor.1'. netlink: 4 bytes leftover after parsing attributes in process `syz-executor.1'. netlink: 4 bytes leftover after parsing attributes in process `syz-executor.1'. tmpfs: No value for mount option 'huge˙alma9s' kauditd_printk_skb: 28 callbacks suppressed audit: type=1804 audit(1659322327.237:16379): pid=16719 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.5" name="/root/syzkaller-testdir1570792705/syzkaller.fRwObc/267/bus/bus" dev="sda1" ino=14998 res=1 audit: type=1804 audit(1659322327.287:16380): pid=16719 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.5" name="/root/syzkaller-testdir1570792705/syzkaller.fRwObc/267/bus/bus" dev="sda1" ino=14998 res=1 tmpfs: No value for mount option 'huge˙alma9s' tmpfs: No value for mount option 'huge˙alma9s' audit: type=1804 audit(1659322328.167:16381): pid=16845 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.5" name="/root/syzkaller-testdir1570792705/syzkaller.fRwObc/269/bus/bus" dev="sda1" ino=14993 res=1 audit: type=1804 audit(1659322328.197:16382): pid=16845 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.5" name="/root/syzkaller-testdir1570792705/syzkaller.fRwObc/269/bus/bus" dev="sda1" ino=14993 res=1